The T-cell immunoglobulin mucin 1, also known as kidney injury molecule-1, modulates CD4+ T-cell responses and is also expressed by damaged proximal tubules within the kidney. Both Th subset imbalance (Th1/Th2/Th17) and regulatory T-cell and B-cell alterations contribute to the pathogenesis of autoimmune disease. This study investigated the effects of an inhibitory anti-T-cell immunoglobulin mucin 1 antibody (RMT1-10) in lupus-prone MRL-Fas(lpr) mice. MRL-Fas(lpr) mice were treated with RMT1-10 or a control antibody intraperitoneally twice weekly from 3 mo of age for 16 wk. RMT1-10 treatment significantly improved survival, limited the development of lymphadenopathy and skin lesions, preserved renal function and decreased proteinuria, reduced serum anti-DNA antibody levels, and attenuated renal leukocyte accumulation. Th1 and Th17 cellular responses systemically and intrarenally were reduced, but regulatory T and B cells were increased. RMT1-10 treatment also reduced glomerular immunoglobulin and C3 deposition and suppressed cellular proliferation and apoptosis. Urinary excretion and renal expression of kidney injury molecule-1 was reduced, reflecting diminished interstitial injury. As RMT1-10 attenuated established lupus nephritis, manipulating immune system T-cell immunoglobulin mucin 1 may represent a therapeutic strategy in autoimmune diseases affecting the kidney.
Nozaki, Y., Kitching, A. R., Akiba, H., Yagita, H., Kinoshita, K., Funauchi, M., & Matsumura, I. (2014). Endogenous Tim-1 promotes severe systemic autoimmunity and renal disease MRL-Fas(lpr) mice. American Journal of Physiology-Renal Physiology, 306(10), F1210 - F1221. https://doi.org/10.1152/ajprenal.00570.2013